The Araguaia Spinetail is a recent split in the Synallaxis complex of spinetails. Ridgely & Tudor regarded it as a subspecies of White-lored Spinetail, S. albilora, while Clements classifies it as a subspecies of Plain-crowned Spinetail, S. gujanensis, and Meyer de Schauensee in his "Guide to the Birds of South America" of 1970 regarded White-lored and Plain-crowned as a single species.

The Araguaia Spinetail is found in the vegetation on the borders of the rio Araguaia and especially on the river islands including the Daddy of them all, the Ilha do Bananal, the largest fluvial island in the world.